The present invention relates to a plasma display panel (PDP) of an AC driven surface discharge type.
Recently, there is expectation of realization of the AC driven surface discharge type PDP as a large and thin color display.
FIG. 4 shows a conventional PDP of the AC driven surface discharge type. The PDP comprises a pair of front and back glass substrates 11 and 12 disposed opposite to each other, interposing a discharge space 18 therebetween. The glass substrate 11 as a display side has a plurality of row electrodes X and Y which are alternately disposed in pairs to be parallel with each other at the inside portion thereof. Each of the row electrodes X and Y comprises a transparent conductive film 13a formed by an ITO having a large width and a metallic film 13b formed by a metallic film having a small width and layered on the transparent conductive film 13a for compensating the conductivity of the film 13a. The row electrodes X and Y are covered by a dielectric layer 14.
A projected dielectric layer 14a is provided opposite to the metallic film 13b on the opposite side of the dielectric layer 14. The projected dielectric layer 14a is provided for preventing error discharge in an adjacent discharge cell. A protection layer 15 made of MgO is coated on the dielectric layer 14. On the glass substrate 12, a plurality of data electrodes 16 are formed to intersect the row electrodes X and Y on the glass substrate 11. A fluorescent layer 17 covers the data electrodes 16. The discharge space 18 is filled with rare gas.
A plurality of partition ribs (not shown) are provided between the data electrodes 16. Thus, a pixel cell is formed at the intersection of the row electrodes in pairs and the data electrode defined by a pair of ribs.
The dielectric layer 14 and 14a are formed by applying glass paste including a lead, for example lead oxide (PbO), and having a low melting point on the X, Y electrodes and by baking it. The metallic film 13b is formed by aluminum, aluminum alloy, silver or silver alloy, because the film is required to have a low resistance to compensate the conductivity of the transparent conductive film.
In the conventional PDP, the glass material used in the projected dielectric layer 14a or the baking condition of the projected dielectric layer is limited because of the disposition under the dielectric layer 14.
More particularly, in order to increase the transmissibility of the dielectric layer, a glass having a low melting point is used and is baked at a sufficiently high temperature. However the fluidity of the projected dielectric layer 14a increases because of the disposition under the dielectric layer 14. It is difficult to form the projected dielectric layer into a predetermined shape consequently. In addition, the glass material acts with the electrodes during the baking to generate bubbles in the dielectric layer. The bubbles decrease the pressure resistibility, which may cause dielectric brake down.